The present invention relates generally to a vehicle level detector which detects a change in the level of a vehicle as reflected in a varying relative distance between a suspension member and the lower surface of a vehicle body or carrosserie. More specifically, the invention relates to a vehicle level detector including a fail-safe mechanism which prevents the vehicle level detector from failure in operation even when one of the elements constituting the detector is damaged.
During the running of a vehicle, it is necessary to make a correction for any abnormal variation in the elevation of a vehicle body which exceeds a normal range of elevation change. A conventional detector comprises a reed switch which detects a change in the relative distance between a suspension member and the lower surface of the vehicle body. While the reed switch is arranged to be switched on and off in accordance with a varying elevation of the vehicle body to thereby detect such variation, the switching of the reed switch which is frequently repeated as the vehicle body moves up and down causes an increased amount of wear of a movable switch contact, giving rise to a poor electrical contact. This also degrades the durability, and hence such a switch cannot be used over a prolonged period of time.
In the meanwhile, the vehicle level detector is normally secured on the vehicle body and is connected to the suspension member with a link mechanism for detecting the relative positions of the vehicle body and the suspension member. Since the link mechanism is subject to road shock and so on with the vehicle body and the suspension member, it is liable to be damaged. When the link mechanism is damaged, the vehicle level detector tends to fail in operation to place the vehicle in an unstable condition.